3876 Chem. Commun., 2011, 47, 3876–3878 This journal is c The Royal Society of Chemistry 2011 Cite this: Chem. Commun., 2011, 47, 3876–3878 A ‘‘plug-and-play’’ approach to the preparation of transparent luminescent hybrid materials based on poly(methyl methacrylate), a calix[4]arene cross-linking agent, and terbium ionsw Christopher R. Driscoll, a Brodie L. Reid, a Matthew J. McIldowie, a Sara Muzzioli, b Gareth L. Nealon, a Brian W. Skelton, c Stefano Stagni, b David H. Brown,* a Massimiliano Massi* a and Mark I. Ogden* a Received 14th December 2010, Accepted 4th February 2011 DOI: 10.1039/c0cc05570k A novel methodology to prepare transparent luminescent hybrid materials is reported. Using a calixarene ionophore as a PMMA cross-linker avoids problems, such as phase segregation, and produces a polymer monolith that can be loaded with the metal ion required for luminescence post-synthesis. This approach is versatile and will simplify the production of such materials. Hybrid inorganic–organic materials offer the advantageous combination of the functional properties of the guest metal centres, such as luminescence and/or magnetism, with the thermal and mechanical properties of the host polymeric matrix. 1 Particular attention has been devoted in the last decade to the preparation of transparent polymeric materials exhibiting luminescent properties, 2 as these find applications in a variety of fields, viz. light emitting devices, optical displays, tuneable lasers, and sensors. Amongst the various classes of potential inorganic guests, luminescent lanthanoid compounds are particularly attractive due to their line-like quasi-monochromatic emissions in the visible or infrared spectra, 3,4 and their potential application in non-linear optics, 5 and as a result they have been used for the fabrication of such hybrid materials. 6,7 We have also recently shown that lanthanoid hydroxo clusters can be used for the fabrication of transparent, reinforced, emissive materials. 8 The challenge in preparing these types of hybrid materials is the tendency towards phase segregation of the inorganic component from the organic polymer. 9 This undesired phenomenon leads to a loss of homogeneity and transparency, significantly decreasing the quality of the final material. Various strategies have been proposed to overcome this, 6 including: (i) functionalisation of the lanthanoid complexes and nanoparticles with suitable solubilising groups; (ii) direct attachment of these compounds, via covalent cross-linking, to the polymeric chains. As part of our work focused on the preparation of transparent hybrid materials, we have turned our attention to the use of calix[4]arene sensitised lanthanoid complexes and their incorporation into polymeric matrices. Calixarene- containing polymers are not common, but have been accessed by functionalisation of a pre-formed polymeric material, 10–13 and by the reaction of a calixarene monomer. 14–23 The bulk of this work focuses on using the well known behaviour of the calixarenes as receptors for the absorption of target species including cations, 13,17,18 anions, 11 biological molecules, 10 and neutral organic species. 14,16 We have exploited the allyl groups at the upper rim of the calix[4]arene 1H (Fig. 1) to form poly(methyl methacrylate) (PMMA) cross-linked with luminescent lanthanoid complexes of 1 À . The advantage of our procedure is that it does not require the pre-formation of the calix[4]arene metal complex, and instead introduces a two-step procedure to obtain these hybrid materials. As depicted in Scheme 1, firstly, methyl methacrylate (MMA) is polymerised in the presence of cross- linker 1H. Secondly, the cross-linked polymer is swollen with a solution containing a suitable lanthanoid salt, which can penetrate the PMMA material and coordinate to the calix[4]arene ligands within. Subsequent swelling (i.e. washing) steps and Fig. 1 The structures of the allyl functionalised (1H) and p-tert-butyl (2H) calix[4]arene trisamide ligands. a Department of Chemistry, Curtin University, Bentley 6845 WA, Australia. E-mail: m.ogden@curtin.edu.au, d.h.brown@curtin.edu.au, m.massi@curtin.edu.au; Fax: +61 8 0266 2300; Tel: +61 8 9266 2483 b Department of Physical and Inorganic Chemistry, University of Bologna, viale Risorgimento 4, 40136 Bologna, Italy c School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley 6009 WA, Australia w Electronic supplementary information (ESI) available: synthetic details for 1H; X-ray structural data of [Tb(1)(DMSO)][ClO 4 ] 2 ; emission and excitation spectra; excited state lifetime data. CCDC 801658 contains the supplementary crystallographic data for this paper. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c0cc05570k ChemComm Dynamic Article Links www.rsc.org/chemcomm COMMUNICATION Downloaded by CURTIN UNIVERSITY OF TECHNOLOGY on 16 March 2011 Published on 18 February 2011 on http://pubs.rsc.org | doi:10.1039/C0CC05570K View Online